Common apparatuses for modifying the lift characteristics of an airfoil for low speed operation is the use of aircraft wing leading edge devices, often referred to as leading edge slats which either pivot or slide forwardly and downwardly from the leading edge of the aircraft wing to a deployed position. Often these leading edge slats are supported by a plurality of track assemblies, each of which is positioned chordwise (fore and aft) inside a wing cavity formed by the upper and lower surfaces of the aircraft wing. Each of the support tracks may engage an arm extending rearwardly from the slat which slides within the track during retraction and extension of the wing slat. These slat tracks may have a curved cross-sectional configuration to guide the slat forwardly and downwardly during deployxent. In order for the trailing edge of the slat in the retracted position to be properly aligned with the upper surface of the wing, it is important that the slat tracks be aligned spanwise along the wing. Any misalignment of these tracks may disrupt the flow of air over the surface of the wing.
In order to permit alignment of the slat tracks, conventionally the slat tracks have been connected to the wing by means which are adjustable to permit repositioning of the slat track relative to the wing. One device utilizes a threaded vertical shaft connected at opposite ends to the slat track and wing, respectively. An upper end of the shaft is threadably engaged to a threaded portion of the slat track and rigidly secured thereto by a threaded nut engaged against the slat track. The other lower end of the shaft is slideably disposed through an opening in the wing assembly wherein the shaft includes at the lower end thereof a radial member integrally attached thereto to prevent retraction of the shaft from the wing assembly opening. The shaft includes a second nut threadably attached thereto at the lower end to engage the wing assembly between the radial member and the second nut. Lockwires are used to prevent unwanted rotation of the first and second nut. In order to adjust the position of the slat track relative to the wing assembly, the lockwires are removed, both the upper and lower nuts are loosened, and the shaft is rotated relative to the slat track and wing assembly causing the slat track to move relative to the wing assembly depending upon the direction of rotation of the shaft. The upper and lower nuts are retightened and the lockwires are reengaged. It is difficult, however, to obtain a precise positioning of the slat track because tightening of the upper and lower nuts about the shaft causes some rotation of the shaft relative to the wing assembly and slat track. Therefore, in order to obtain the desired positioning, it is necessary to estimate the amount of rotation which will be imparted to the shaft due to retightening of the upper and lower nuts, and then to adjust the position of the shaft beforehand to compensate for this subsequent shaft rotation.
In commercial aircraft, the wing cavities where the slat track supports are located are filled with a maze of hydraulic lines, electrical cables and air ducts. Due to the quantity and size of these cables and lines, access into the wing cavity area is severely restricted. A common access port into the wing cavity area is through the lower surface of the wing which is typically covered by removable wing panels. In reference to the aforementioned slat track supports, access to the upper nut is particularly difficult due to the distance between the opening of the access port and the upper nut. This difficulty in accessing the upper nut location, combined with the problem of obtaining proper slat track positioning while tightening the upper and lower nuts, makes accurate alignment of the slat tracks difficult.
Other conventional variable length linkages which have been disclosed include U.S. Pat. No. 4,218,156--Logan, wherein there is disclosed a mechanical linkage comprising a threaded shaft having a first clevis integrally attached thereto at one end thereof, and a second clevis having an integral boss tapped for receipt of the other end of the threaded shaft therein. The boss includes an hexagonally shaped exterior surface for receiving a keeper therearound which is prevented from rotation by a nut threadably engaged to the shaft and tightened against the keeper.
In U.S. Pat. No. 2,704,682--Davis, there is disclosed an apparatus for securing rolling casters to hollow tubular members of furniture legs and the like, wherein upper and lower wedge members of the caster are caused to compress a wedge piece therebetween causing the wedge piece to expand radially against the inner surface of the tubular member.
In U.S. Pat. No. 4,092,080--Bradley, Jr., there is disclosed an adjustable length linear rod comprising an externally threaded male member engaged within an internally threaded female member. The male member is secured against rotation within the female member by an anti-rotation means comprising two semi-circular conical members having key portions which engage slots in the female member The semi-circular conical members are frictionally engaged by a conical member in cooperation therewith by means of a threaded nut tightened thereagainst.
In U.S. Pat. No. 2,999,706--Wilcox, there is disclosed an apparatus for locking a first tube within a second tube wherein axial rotation of a shaft engaging the first tube causes two opposing wedge members to compress a wedge piece therebetween thereby radially expanding the wedge piece against an inner surface of the second tube.
In U.S. Pat. No. 4,181,280--Bowman, there is disclosed a bell assembly for adjusting the height of a chair wherein the bell assembly is threaded onto a support post slideably located in a hub, and the bell assembly is rotated to regulate the height of the support post relative to the hub.
In U.S. Pat. No. 2,433,617--Marsilius, there is disclosed an apparatus for removably securing a guide pin to the bed of a die-set or the like, wherein the lower end of each pin includes a threaded shaft having disposed therein opposing inwardly tapered members. The inwardly tapered members define a recess for receiving flexible members therein which are compressed and expanded outwardly against the bed of the die-set when the shaft is rotated and the opposing tapered portions move toward each other.
In U.S. Pat. No. 4,068,858--Harrison, et al, there is disclosed a bicycle handlebar stem comprising an outer hollow tubular member which receives therein an inner tubular stem. The hollow tubular stem includes a shaft therethrough for engaging at the lower end of the tubular stem a wedge member in a tapered base portion of the tubular stem. Rotation of the shaft causes the wedge member to become lodged in the tapered bore portion.
In U.S. Pat. No. 2,947,556--Wenger, there is disclosed a vertically adjustable device for supporting a music rack comprising an inner tubular member longitudinally disposed within a hollow outer tubular member. A frustrum-shaped plug is spring biased against the inner surface of a tapered skirt depending downwardly from the inner tube to urge the skirt against the inner surface of the outer tube in frictional engagement therewith.
In U.S. Pat. No. 2,878,042--Trimble, there is disclosed a golf cart having upper retaining members which are adjustable to fit around a golf bag and which secure the golf bag to the cart. The clamping members are secured together in an adjustable relationship by an adjustable wedge member which when moved in an upward direction against a wedge-shaped guide causes radial displacement of the wedge members forcing the retaining members together.
In U.S. Pat. No. 2,584,614--Rasmussen, there is disclosed a clamping means for a square-shaped tool bar comprising a V-shaped member for receiving a first set of opposing adjacent surfaces of the tool bar therein, and opposing wedge members having opposing inclined surfaces which engage a second set of opposing adjacent surfaces of the tool bar. Movement of the wedge members toward each other causes displacement of the tool bar against the V-shaped member in engagement therewith.
In U.S. Pat. No. 3,175,455--Reddy, there is disclosed a self-locking expansion bolt for engaging a plate to a base member, comprising a threaded bolt disposed within a frustoconical wedge member which in combination with an inner surface of the base member defines a recess for receiving frustoconically shaped wedge pieces therein. Placement of the self-locking expansion bolt within an opening in the base member, and rotation of the bolt causes movement of the wedge members against the wedge pieces displacing the wedge pieces radially against the inner surface of the base member
In U.S. Pat. No. 3,501,183--Stratienko, there is disclosed a self-innerlocking wedge device comprising an outer thrust collar having an axially tapered inner surface for receiving a shaft or the like therethrough. A recess, defined by the tapered inner surface of the thrust collar and the outer surface of the shaft, receives a wedge member therein. Due to the difference in coefficients of friction between the inclined surface and straight surface of the wedge members, axial movement of the shaft causes deflection of the wedge surface against the thrust collar securing the shaft to the collar.